Development in Earth Science Volume 1 Issue 1, September 2013
www.seipub.org/des
Analysis of New Atmospheric Aerosol Particles Formation; Case Study of Seasonal Variability of Number Concentration in Rural Region of Poland in 2009 Janusz Jarosławski1, Barbara Kopcewicz2, Aleksander Pietruczuk3, Jerzy Podgórski4 and Izabela Pawlak*5 Institute of Geophysics, Polish Academy of Sciences 64 Księcia Janusza, 01-452 Warsaw, Poland. 1januszj@igf.edu.pl; 2barbara@igf.edu.pl; 3alek@igf.edu.pl; 4jp@igf.edu.pl, *5izap@igf.edu.pl Abstract Measurements of concentration of gaseous pollutants have been performed since 1996 and aerosol particulate matter PM10 since 2007 at Belsk Observatory, the rural site in Poland. Simultaneously operated in 2009 Scanning Mobility Particle Sizer (SMPS) spectrometer provided information on particle number concentration and size distribution in the range of 10.4 to 467 nm. The information related to concentration of gaseous pollutants and particulate matter with a diameter below 10 µm (PM10) describes well condition of the atmosphere at sampling site. To describe processes of nucleation and accumulation of aerosol particles the sources of ultrafine particles data obtained in SMPS measurements for the year of 2009 were investigated in terms of annual, weekly and diurnal cycles. The sampling site was influenced by local anthropogenic sources, such as traffic and domestic heating. The size distribution and number concentration of particles varied with season. The largest values of number concentration were observed for particles in the ultra fine size range (nucleation and Aitken particles) for months with large values of the transparency index G/G0 suggesting that solar radiation has a substantial influence on new particle formation during photochemical gas-to-particle conversion. Keywords Air Pollution; Atmospheric Aerosol; Gas-To-Particle Conversion
Introduction In the recent years, the subject of regulation of particulate substances in ambient air has become an important issue in pollution control resulting from a significant role of atmospheric aerosol played in interactions with atmospheric radiation, participation in chemical reactions and cloud formation processes (e.g., Charlson, 1969; Stevens and Feingold, 2009; Lohmann and Feichter, 2005). For the last decades attention has been paid to the concentration of
respirable suspended particulate matter (PM10 and PM2.5) due to its potentially hampering health effect (e.g., Stieb et al., 2002; Nemmar et al., 2003). However, some studies (e.g., Schwartz et al., 1996; Ferin et al., 1991; Donaldson et al., 1998; Nel, 2005; Pope et al., 2002; Pope and Dockery, 2006) suggest that some ultra fine particles can penetrate directly into the lung tissue and may have a much greater physiological impact than fine and coarse aerosol particles of the same composition. This is the reason that the structure and number size distribution, beside the total mass concentration of suspended particles, is an important subject of environmental studies (e.g., Kulmala et al., 2004; Holmes, 2007; Van Dingenen et al., 2004). The complete information on concentration of particulate matter and gaseous pollutants, the size distribution as well as the physical and chemical properties of the atmospheric aerosol are useful for the effective emission control. However, an increasing number of theoretical and experimental studies describe the condition of ambient air mostly at urban or industrial sites (e.g., Shi et al., 2001; Wehner and Wiedensohler, 2003; Charron and Harrison, 2003; Hussein et al., 2004; Imhof et al., 2006; Kerminen et al., 2007; Wang et al., 2010; Řimnáčová, et al., 2011; Lonati et al., 2011; Shen et al., 2011). There is insufficient information on rural regions representing different environments and climates. Such studies could be very useful to describe chemical and physical processes observed in the atmosphere and which would not be overlapped by severe industrial pollution. Some important information on the atmospheric aerosol properties in Europe has been provided during several European projects such as PARFORCE on the marine environments (O’Dowd et al., 2002), BIOFOR for biogenic aerosol production (Kulmala et al., 2001). The
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